1. Field of the Invention
The present invention relates to a surgical stapling and cutting instrument adapted for use in the diagnosis and therapy of pathologies treated by stapled resection. More particularly, the invention relates to a retainer for a cartridge module used in conjunction with a surgical stapling and cutting instrument.
2. Description of the Prior Art
Within the field of surgery, the need to surgically seal tissue and to cut tissue is quite commonplace. Sealing of tissue may be accomplished by numerous sealing devices, for example, surgical staplers. Cutting of tissue may be accomplished by numerous cutting devices, for example, scalpels and surgical scissors. Stapling and cutting of tissue in several steps during the surgical procedure adds time to such procedures. In order to reduce procedural steps and ultimately the time necessary for various surgical procedures, instruments have been developed which simultaneously apply staples and cut desired tissue. As those skilled in the art will certainly appreciate, it is desirable to provide stapling and cutting instruments capable of performing multiple stapling and cutting routines during a single procedure.
Some current surgical instruments provide stapling and cutting mechanisms that operate in the same direction during device actuation, or firing. For instance, staple formation and tissue cutting occur along the same plane on the tissue. These instruments generally utilize an anvil, which holds staple pockets (or staple forming surfaces) and a washer, and a housing assembly, which holds staples and a knife. In these prior instruments, the anvil is generally a permanent element of the instrument and the housing assembly is either a permanent element (single-fire device) or a reloadable element (multiple-fire device). Tissue is captured between the anvil and the housing assembly of the device. Actuation of the instrument moves the staples from the housing assembly toward the anvil. The staples puncture the captured tissue and then contact staple pockets on the anvil, which form the staples into desired shapes to seal the tissue. In conjunction with the staple formation, actuation of the instrument also moves the knife from the housing assembly toward the anvil. The knife pushes the tissue toward the anvil and, upon contact with the knife and the washer on the anvil, cutting of the tissue is facilitated. Cutting in this manner is similar to cutting on a cutting board.
The washer is generally made of a resilient material and is a permanent element of the anvil. The knife is either a permanent element that actuates within the housing assembly or a reloadable element with the housing assembly. For single-fire instruments, the washer and knife are discarded with the complete instrument after firing. Single-fire instruments present higher associated costs since a new instrument is needed for subsequent firings. For multiple-firing instruments, the housing assembly is discarded and a new housing assembly is reloaded while the anvil with accompanying washer is reused for subsequent firings.
These prior surgical stapling and cutting instruments often include a retainer adapted for preventing movement of the staples or knifes. For example, many of these retainers snap onto the outside of the cartridge housing or slip into the knife slot of the cartridge housing. Unfortunately, these prior art retainers are easily dislodged allowing components, in particular the staples, to move out of position.
As such, it is apparent currently cartridge modules includes a variety of shortcomings. As a result, it is desirable to provide a cartridge module for surgical stapling and cutting instruments adapted to include an anvil coupled to a cartridge housing within which are located various moving components such as a knife and staples. The present invention provides a cartridge module for a surgical stapling and cutting instrument which includes a retainer to prevent movement of the modules components prior to use.